Helmstaedter C, et al. - Physicians designed this study to validate the Cognitive Problems in Children and Adolescents Questionnaire (KOPKIJ, German: Kognitive Probleme bei Kindern und Jugendlichen), a proxy report measure for recognizing cognitive problems in pediatric patients with epilepsy. They concluded that the parents' impressions of children’s cognition obtained through the KOPKIJ only in part reflected the neuropsychological cognitive status of children and adolescents with epilepsy. They seemed rather determined by the children’s behavioral problems, which in real life situations indeed often co-occur with cognitive impairments. Aspects of epilepsy only marginally affected the parents’ ratings of their children’s cognition.

• The physicians standardized anonymized data sets from 279 pediatric epilepsy patients in regard to the KOPKIJ results of 352 healthy children and adolescents.
• The KOPKIJ was associated with objective routine neuropsychological assessment (NPY), and to two subjective measures, the Child Behavior Checklist questionnaire (CBCL), a proxy rating by the parents, and a questionnaire for self-perceived health-related quality of life in children and adolescents (KINDL).

• Three scales “basic functions”, “academic skills”, and a “total score” were differentiated following principal component analysis of the KOPKIJ’s normative data, which demonstrated problems in 35%, 33%, and 32% of the children.
• In 23%, low IQ was evident, objective impairments in at least 1 major cognitive domain in 65% of the patients.
• Behavior (CBCL) and quality of life (KINDL) were impaired in 40% and 21% of the patients.
• Separate regression analyses demonstrated that objective cognitive performance (IQ, language, visual-spatial functions) explained ~30%, behavior (CBCL) and coping with the disease (KINDL) about ~40%, and clinical features (age at onset) 5-8% of the variance of the KOPKIJ scales.